SA97180186B1 - Process and plant for metallizing cast-iron pipes - Google Patents

Abstract

Abstract: This invention relates to a plant unit for metallization of a metal tube produced by continuous vertical casting from the top, which is displaced vertically in a continuous process, and includes along the path of the tube a metallurgical station with a passage for the tube, and a fence (perimeter range) for metal (6), spray guns (11), fixed within the perimeter on a rocking plate (oscillating plate) (10) surrounding the track, and a means of supplying packing material to each gun (12), and a device for causing the mounting plate to vibrate and for moving the pistols within the perimeter with a vibratory (oscillatory) motion, whose frequency and angular amplitude provide Forming a casing of consistent thickness.

Description

¥ Process and unit plant for metallizing cast-iron pipes Full Description BACKGROUND The invention relates to a process for metallizing metal substrate materials and more specifically to hot metallization of pipes; In particular, pipes made of cast-iron, which are obtained by vertical casting Cal ° Z. Among the well-known methods of hot metallurgy are; We mention the following: ) Hot modified galvanization. Continuous coating of metal sheets with alloys Al-20 or ZnAl. Methods for thermal spraying with Zn or Hd alloys7. z 0 > coating the tubes with zinc. Note that existing solutions based on galvanization have the following disadvantages. The modified galvanization, in particular, covers the tube internally and externally, and then the tube is exposed to an increase in temperature. Therefore, what was done as a result of other previous operations that were carried out on the tube at lower temperatures will be affected. he Also, hot galvanizing by moving through a liquid causes a problem 2 that has not been solved until (OY) Tolerance or resistance with regard to the liquid bath between the vertical pipe FVA

liquid metal; As well as the problem of maintaining the bathroom so that it is clean (without the presence of met; matt: a molten sulphide mixture) and has a stable and stable composition over time. Whereas, cold metallization associated with annealing (heating followed by slow cooling) may ensure good distribution if the hardening conditions for surface preparation of the tube are suitable and it may also require heat treatment in an inert atmosphere. Therefore, the costs of the mentioned treatment cycle may be huge, and therefore they show limited advantages from the economic point of view. Also, the tube to be coated or coated; Which is produced after continuous casting. not be rough This makes fixing the paint or cold coat impossible without surface preparation (roughening the surface to accept the paint). In order to achieve a well-distributed coating (coating), it is necessary to use a tube that does not have an oxide shell, and the operating temperature is high, or the tube treatment time must also be long. GENERAL DESCRIPTION OF THE INVENTION z vo The invention aims to prepare a uniformly dispersed coating or coating which has good shock resistance. Furthermore it; Another object of the invention is to prepare a good gail 0 on the outer surface of a tube of variable diameter and position; which is carried out continuously in a vertical direction without being subjected to rotation; While protecting the tube from being subjected to thermal annealing. : .: in addition to; The objective of this invention is to prepare a coating or cover that is "self-adhesive" in terms of exposure to any damage.

¢ Finally; The goal of this invention is to prepare a coating that participates in corrosion resistance in the case of its presence underground. Therefore, the invention relates to a process for metallizing a metal tube produced by vertical casting which is displaced vertically by a continuous process with an upward motion; The process is characterized [Ll] consisting of: ° Cooling the tube in an oxidation-inert atmosphere to a temperature of 700,000 to 00 °C; f spraying a zinc-based mineralization alloy over the tube; coolant to the preset temperature; With the help of a group of spray guns so that they surround the path of the pipe to be metallized. 1 According to a particular characteristic of this invention; The spray guns are subjected to oscillation or vibration around the tube path with a frequency and angular oscillation amplitude consistent with the velocity of the tube displacement in order to obtain a coating or casing of consistent or uniform thickness. The invention also relates to a unit for metallizing a metal tube produced by continuous vertical casting from the top, which is vertically displaced by a continuous process; which is characterized as 1° includes; Along the path of the pipe there is a metal station with a passage for the pipe; a fence (perimeter band) metal; spray guns fixed inside the said fence on a rocker (vibrating plate) surrounding said track and means for supplying metal to each gun; and a device for causing the mounting plate to vibrate and for sliding the guns into the aforementioned fence with a vibratory motion; whose frequency and angular amplitude ensure the formation of a symmetrical thickness (53 m).

The invention furthermore relates to a metal tube obtained by vertical casting; Which is characterized by having a mineralization coating produced by the specified process and according to a special characteristic of cs AT, the spray guns are three of the number Cua - and are installed on the board at an angle of 0171 degrees lad between each of them. According to another special characteristic; The spray guns are flame guns or z: arc guns. According to another special characteristic, the metallizing material (or metallizing) is a wire of ZnAly alloy, and the means for supplying or supplying the mineralizing material includes 0 > for each gun a wire store and a tool for unwinding the wire coils and works by the vibrating or oscillating movement of the plate that is fixed He pistols. Brief Explanation_of the Drawings It should be noted that the invention will be more fully understood by reading the following description; What is given is for representation only and by reference to the accompanying drawings; in which: Fig. 1 represents a schematic view of a vertical section of a metallurgical unit of the subject of the invention; Fig. ?: a schematic cut-out view along the Y-Y line of Fig. 1; Fig. ©: a partial lateral schematic view of the metallurgical unit shown in Fig. 1; z Fig. 4: a partial cut-out view of a flame gun of the unit; Figure 10 shows a high-resolution micrograph of a coating produced by the process Cg sess z' - Invention: M

Detailed description It is clear from Figure 1 that the metallurgical unit has ; along the route of tube 1 which results from continuous vertical casting from above (not shown) and above that unit; Column 1 to pass the tube '1 that has been manufactured; Which is injected into it through the ill (stream) CY 0 nitrogen to allow tube 1 to shift between the outlet of the casting unit and the metallurgical unit in an atmosphere that protects the surface of tube T from oxidation. 0 since column 1 has a subscript ? which the tube gradually cools as it moves up from 0101°C to 0001°C and an upper part; Water-cooled located directly below the metallurgical zone within which the temperature of the pipe is reduced from 1000°C > to a temperature between 006°C pve A sliding mask © made of heat insulating material is installed Jala Column 1 at the level of the joint between the lower part 7 and the upper part; For the column, as its movement inside the upper part 4 allows cooling the tube 1 to be adjusted by placing it between the tube and the wall of the said cooled part. | vo and Jef install column 1 fence (band) metal 76 incorporating a bottom 7 inclined downward; from the center to the periphery; It is equipped with A-channels (absorbent channels). In the central part cal the bottom 7 is attached to an anti-drop cover 9 through which the tube 1 to be coated or coated passes with minimal movement in order to prevent the sprayed metal product that has not adhered to the wall of the tube from falling towards the bottom of the unit. : : Y. In addition, the fence shall have, in addition, a rocker plate 01 on which spray guns such as metal flame retardant guns are fixed. 11 ab b

: While each hexagon is equipped with a metal wire 11 in a process that will be described by reference to Figures 1 to 4. Noting that the hexagons 11 weigh, for example, three in number and are as z on the plate 01 At an angle of 0171 degrees between each of them. . As each gun sprays a VY fountain of metallurgy over the tube 1 sl | move it up. Z The spray guns can also be arc pistols. How much it can consist of means to turn liquid metal into an aerosol. In any case, flame guns are characterized by the fact that they constitute a thermal technology that does not interfere / or confuse the kinetics of cooling the product. It ensures excellent droplet spraying performance of the alloy because the droplets are not directed away from the substrate; For example Ja in the case of using a bow gun. Knowing that the flow of flame guns is more accurate than in arc guns. Vo is because it only needs one metal wire while crossbow guns need two wires. The upper VE wall of fence 6 also has some absorption channels. Whereas the Fence+ is mounted on a water-cooled casing 17 which allows the mineralized tube to exit the metallurgical unit at a temperature of; 75 2°, which represents a thermal sieve, which unit a prevents it from becoming hotter than Cah©.” 7 Whereas, the unit shown in cross-section in Figure ¥ has a platform (not shown) through which the tube formed passes and a chamber is fixed on it Metal with ring plate .01 YVYA

z : plate 01 is rotated by oscillating or vibrating motion by means of a suitable mechanism; not shown. OLS, also prior to this invention; The aforementioned tablet carries three pistols. 11. We believe that the number three ensures the best compromise between unit cost and uniformity of thickness ° coating or coating. On any Ja the number of pistols may vary from three. The magnitude of the angular displacement of the slab 01 as well as its frequency are a function of the - angle of distribution of the jets VY of the molten metal sprayed with the guns 11 and also the velocity of the tube displacement 1 to allow the laying of a metal layer of uniform thickness. 0 z while each metal gun 11 has a means of supplying oxygen and gas via Ve via suitable hoses (not shown) to a tool for supplying the metallurgy in the form of AY wire where each tool includes a 710 wire stock And a tool for decoiling wire rolls referred to by the general reference number 71, which is intended to carry the VY metallizing wire from the wire stock 01 of the attached hexagon or connected to it OY, taking into account the oscillatory movements (vibration) to which the hexagon 11 is exposed. Installed on the rocker plate. Wire 11 usefully consists of an alloy of 0 to 9610 Al and it is also possible to use lined wire consisting of a zinc core surrounded by an aluminum sheath; And in that All and after fusion; We may obtain a Zing Alls alloy as the lined wire consists of an ammonium core and a zinc sheath. ra

While choosing the lined wire or the best alloy to reach the desired metallurgical composition of type 1-2 Zn,Al for: The figure shows “one of the spray guns 11 installed on the vibrating plate 01 of the industrial unit (the unit) and also shows the wire store 01 and wire decoiler or wire unwinder YY oe The metallizing wire 17 is placed in coil form inside a YY cylinder ie a cylinder of a type with standard characteristics for oil products; Equipped with a YY central core on which the wire coil (not shown) is held inside the drum. 1 Next to the cylinder shall be mounted a YO frame incorporating a bracket 776 which supports or anchors a wire straightener 77 with four pins or rollers to which a YA input cone of VY wire is attached which It is directed towards cylinder 77. At the outlet of the wire straightener “YY” a group of wheels is installed” A first wheel “Yo” which is fixed on an inclined support ©1 fixed at point PY of the upright vertical part of the bracket (SHYT) A second wheel TE so that Fed or oscillates around a point close to point PY To fix the first wheel 1 by means of a movable FO support or bracket from which the FTE hangs Weight 37 is fixed with a 7 “bar hinged on the bracket A third YA wheel is attached to redirect the wire towards the board; it is mounted above the vibrating plate CO 9 building das ll not shown Co oo ron x m bm : And for the exit of the third wheel YA is a wire straightening tool A second four-reel 460.

A

A fourth wheel 4 or a wheel to insert the wire into the hexagon shall be installed at its rear end which is mounted on a pivot support (rotating oa of the hexagon or against a hole: .01 according to the vibration or oscillation of the plate 11 about an axis) and allows By adjusting the inclination of the metal wire, which is YY from the storage coil that is housed inside the cylinder VY, the metal wire is loosened and for the first time it is inserted into the straightening tool 17; passes over the wheel YA passes through an insert neck ° as it overlooks the YA and again over the third wheel FE the first;7; Then under the second wheel that supports the second wheel YO the arc alia is pulled by the weight 37 that exerts a force on the wire 0 and the wire is tightened again by means of the second wire straightening tool with four rollers m EE, after passing over the fourth wheel 11 and entering the flame gun, it has a tool to rotate the wire so that it enters the melting area. or a servo motor incorporating a gear generator; as well as a conveyor assembly with reduction gears, wire winding bobbin and pneumatic bobbin clamping device; which; By means of pistons or pistons that ensure the fixation of the wire between them. {5} which has a base of 1. The flame gun of, as clearly shown in Figure ami A, is provided at its opposite end to the metal slot 47 with a strap 01. fixed to the board te the girders 44; And 00 is mounted on them in a vibrating or oscillatory pattern, a forked member (it has an end

Yo. . 44 fork end) 0) supports or holds the fourth input wheel bb

1 oriented radially with respect to the rocker plate 00 since the beams are £9 and

Ye at the entrance of the wheel ;; On 11 moreover a guide 0 is mounted for the metal wire

OY manifold is positioned as close as possible to zone EA of the support 00 as the crossbar .

The fusion AY of the gun 21 shall have an axial passage 1© through which the wire passes prepared 11. In addition, the gun shall have connections or connecting sleeves 88; or to receive hoses; not shown To supply the gun with gas and oxygen.‎ . It is restricted that the gas used be propane; Or acetylene or natural gas

VV in the direction of the melting zone of the spray gun 70 Al Ji alloy, therefore, 01 is done so that it melts into small droplets and sprays. Whereas, the tube or pipe 1 to be metallized, which is present or prepared at a degree Celsius and is free of Ave at about AT set operating temperature; In the sense of surface oxides as a result of the nitrogen atmosphere that surrounds them in the mineralization zone; receives a fountain of M, to which it attaches. Zn AL fired by Pistol 11; It consists of a spray of small droplets of 1

OY barrel In addition to the reciprocating rotational movement of the Jas guns, and as a result of the movement, it can ensure a good consistency of the thickness of the resulting coating or coating. 7 m / m

VY: but the alloy remains liquid on the pipe; However, it does not slip as a result of the effect or action of the capillary property and also as a result of the rapid surface oxidation and hardening of the surface of the outer casing

output as well. ~~ . During the total cooling phase following the metallization phase, which extends or lasts for about 2 yo minutes, the alloy reacts with the cast iron forming the pipe material; Thus, alloy structures of type Fey, Al) charged with a small percentage of interlayer zinc are formed. Thus, the result is a pipe coated or coated with an external coating, which is formed so that it is completely connected and adherent. ', Whereas the suction device attached to the perimeter range or enclosure and particularly connected to the suction tubes oA equipped at the bottom 7- and the suction tubes (Vo) fitted in the upper wall VE of the said perimeter range allows suction of alloy droplets that did not reach a tube or pipe For example, a certain amount of numerical data related to the operating variables and the nature of the metallurgical alloy used is given in the following.Cus the charging or feeding speed of the VY wire is “AREY 5B” and its diameter is millimeters and its linear mass is n/g meter 0 the yield is 0% LS previously mentioned; the wire is made either in the form of the ingot Zngs or in the form of Ye: lined wire with a zinc core; which makes it possible to obtain an ingot and Znys FY A tiles

\Y is equal to 90 degrees. 11 gal The angle of rotation of a millimeter hexagon was 710 The step taken in one revolution was 100 grams / meter and from the tests carried out it is possible to obtain a coating

Zngs g/m2 of Yepple alloy ©0800 sq to As shown in Figure ©; The microscopic image of a section through the coating obtained clearly shows the formation of a well-distributed brightness. In that form, indeed; It can be seen that it may be a distributed alloy interface

SN Zn Al between the wall of cast iron 65 and a good TY coating layer JSG A and during the crash endurance tests carried out on the coated pipe, it was of L (durable strength unit); In other words, the deformation of the pipe without 1960 can achieve values up to damage to the coating. The corrosion properties of the resulting coating are equivalent to the properties that may be produced from We of the substrate and with the same alloy. Bal of hot galvanizing on the same while painting; The pipe does not undergo any annealing effect. Hence, the metallization process subject of the invention has the following advantages in relation to what the field has reached. As it allows controlling the thickness of the metal coating by adjusting the feeding or charging speed

FYA Metallized Alloy Wire.

Ve It also allows the possibility of obtaining a continuous linear coating. It allows a well-distributed anti-corrosion coating. It also allows the application of a sealant due to the added roughness of the smooth pipe from the beginning by means of a metallization coating. Finally, it allows the use of lined wires as well as other alloys

Ya

Claims (1)

Vo Protection Elements A process of metallizing a metal pipe produced by vertical casting, which is displaced vertically 1-1 by a continuous process with an upward motion; The process is characterized by the fact that it consists of: Y 00 to 001 cooling the tube in an oxidation-inert atmosphere to a temperature r ° C; and t spraying a metallurgical alloy based on zinc over the tube” cooled to the aforementioned 1 °C temperature with the help of a set of spray guns so that it surrounds the path 1 of the tube to be metallized. v ?- The process subject of the invention as in element 1; Whereas, the alloy based on zinc ZoAlix 1 is the process Y subject of the invention as in element 1; Where the metallizing alloy is in the form of *1-* wire. The process subject of the invention is as in element 1- where the said wire is a wire of 1-4 zinc. 961 alloy includes between # and | Y © Process subject matter of the invention as in item 1; Whereas, the said wire is a wire of O = 1 .Zngs Als Y FVA 1 0 : \>- The process subject of the invention as in the element (©) where the said wire is a Lined wire consisting of a zinc core surrounded by an aluminum sheath that allows the alloy to be obtained Alsoss v and m7 after melting. 1 "- The process subject of the invention as in item 1a where the said wire is a Lined wire consisting of an aluminum core surrounded by a zinc sheath. 1E - plant unit for the metallization of a metal tube produced by continuous vertical casting from the top and which is displaced vertically by a continuous process; It includes; along the path of the tube; metallurgical station v is a passage for the pipe; and fence (perimeter band) metal 1) spray guns (11); installed inside the band t Surrounding on a vibrating plate (01) surrounding the sights and a means of supplying each gun with material Metal (Y) 1) and means (70; (YY) to provide each gun with metal material (VY) and means 1 to vibrate the mounting plate and to slide the guns within said enclosure with a vo-vibratory (oscillatory) motion; Its frequency and angular oscillation amplitude are affected by the formation of a thick shell A is consistent. z \ 4- LS plant unit in element 8; As the passage of the pipe (T) to be painted 0 includes an underscore ("); water-cooled upper (4); Slider mask (0) to adjust cooling CE) The pipe (1) to be placed at the joint between the lower part (©) and the upper part r OS The perimeter metal band (fence) (76) is above the said upper part (£) and is mounted on it ° Water-cooled casing (07) 0 ‎FYA VY 0-1 plant unit as in the oh element where the spray guns (VY) are three of v where is the number and are installed on the board at an angle of 071 degrees between each other. plant DAHU-11 1 as in item A where the spray guns (VY) are guns 7 flame or bow guns. 1-1 plant unit as in element Cus A the metal sale (VY) is Y wire is ZnAl alloy and the means for providing the metallizing material are included for each gun v Wire hopper (01) and wire unwinding tool (YY) AS all vibrating or oscillating t of the plate (V4) on which the guns are fixed and which are equipped with a means to rotate or guide ° behaviour. 0” 1 plant unit as in element A since the surrounding metallization band (7) includes Y bottom (Jala) v down 6 from the center to the outer circumference; equipped with suction holes (MN) (holes 1 absorption); and that the aforementioned bottom (V) is connected at its center with a cover (3) to prevent the fall of the pipe 1 through which the pipe (1) passes to be coated or coated with the minimum amount of ° Movement in order to prevent the sprayed mineral product that did not stick to the wall of the tube from falling 1 toward the bottom of the unit. : F.V.A 0 VA with product (11) as the means of supplying each gun (A) as in item plant unit 4-1 and a tool for removing the said wire from the store and transferring it (01) includes a wire store (VY (Aided) 1 A) 1) The direction of the opposite hexagon Y since the wire store attached to each VE hexagon as in the element plant unit - 1 includes a cylinder (77) to receive a coil of metal wire with a central core (11) Y on which the coil wire is wound. (YY) 7 Whereas, the metal wire unwinding tool includes the VE as in the element plant Unit 7-1 (01) from the store (VY) is dedicated To move the wire (YA FE) a set of wheels (70; Y) and a wheel (££) to insert the wire supplied by the set (01) up the vibrating plate v into the corresponding hexagon (11); where the insertion wheel mentioned (©8 (FE CY) the wheels 1 Tally are oscillating or vibrating above the hexagon in a direction radial (01) to said plate (10); their direction follows the vibrations of said plate 1 (FA FE eT) as the set of wheels OT as in element plant unit 1 - 1 dae oF) and mounted on a fixed support (VY) bearing the wire (Yr) includes a first wheel le gab and A knee on a vibrating support (0) which (VY) passes under the wire (YE) sec 0: for wire rerouting (PA) and a third wheel (VY) for wire tension (YY FT) Means (AVY) towards the wheel (£2) to insert the wire into the gun (VY) ° YA 1 - plant unit as in element VY wherein the wire unwinding tool is ld between 1 roller (YY) and first wheel (13); conical core (YA) for wire (VY) and the ; First (YY) to straighten the wire and at the exit of the third wheel (8©)» second tool (40) to straighten 3 wire. 1 4- The plant unit as in the element VY, since the means of tensioning the wire (VY) includes carrying (YY) y suspended from the vibrating support (Yo) of the wheel (YE) Atl —Y 1 plant unit as in item V1 wherein the wheel (£2) for inserting the wire (VY) into the stapler (11) is fitted so that it can vibrate or oscillate within a bearing (6A) 7 of the hexagon by means of a manifold (0) and beams (3 00£) mounted radially radially relative to the rocker plate (10); including the beam (00) closest to the fusion zone 2 of the hexagon (\0) on the (eV) path through which the wire passes (7 A) 1-71 a metal tube produced by vertical casting”; Where it has a metallic coating Y is plated by the process of the invention. YY 1 — Operation as in item 1 and also includes vibrating or vibrating the spray guns 1 around the tube track. A: